IAEA to coordinate Pacific monitoring

The International Atomic Energy Agency (IAEA) is bringing together 24 countries in the Pacific Ocean region to help monitor the movement of radionuclides released from the Fukushima nuclear accident.

The accident in March this year on Japan's Eastern seaboard caused an unprecedented emission of radioactive materials to sea, mainly iodine and caesium. A major outflow occurred between 1-6 April when a leak from a trench containing electrical cables caused an estimated 4.7 petabecquerels of radioactivity to be released. Lesser outflows have also continued to occur as run-off from the plant and countryside has taken place, while an unknown amount is due to atmospheric emissions which have blown out to sea.

Many countries in the Pacific region have expressed concern that this contamination could potentially damage their coastal environments and negatively impact communities and economies. This led to the IAEA board approving a technical cooperation project during its annual meeting in June.

The project seeks to harmonise the measurements of various radioisotopes in marine waters, biota, sediments and suspended material so that a more comparable and verifiable picture of the wider ocean contamination can be established. The IAEA will serve to boost local measurement capabilities, and facilitate the exchange of data between countries.

According to the IAEA, despite the fact that radioactive material is expected to be "significantly diluted by time" as it has mixed with the vast body of water in the Pacific, ocean currents will act to transport material throughout the wider Pacific area "for the foreseeable future."

"It is expected that the enormous dilution capacity of the Pacific Ocean will lead to low residual concentrations of radionuclides in ocean waters such that any significant contamination of marine food in coastal waters outside of Japan will not occur," said IAEA technical officer Hartmut Nies. "To date, only caesium -134 and caesium -137 were detected far offshore from the Japanese coast in the prevailing Kuroshio Ocean current at levels of less concern."

The first meeting for the project took place in Australia in August, while a training workshop was held in the IAEA Environmental Laboratories in Monaco from 21-25 November. The workshop led to the adoption of a quality management system and database for the future monitoring efforts. The project is expected to run till 2015, with a first progress report due in 2012.